This is very good question. The explanation is quite technical. What you see is an artifact of the Eclipse platform that WireframeSketcher is based on. Eclipse allows for different project types, so "Project" stands for a simple project, and "Project..." stands for project selection wizard which lets you select from different project types (when available). It all makes sense in Eclipse (which has different project types) but I agree that it's confusing in WireframeSketcher Studio which only has one project type. I'd love to find a way to hide the "Project..." item, but it may not be possible. I'll look more into it.
Jerry23 Apr 2012
Thanks for your reply. Your explanation is quite clear that make me know all these things happened. Yep, I would ignore that "Project..." from now. Thanks again.